/* 分辨率低于768，采用下面的样式*/
@media  (max-width:768px) {
    .nav {
        margin: 100px auto;
        position: relative;
        width: 580px;
        height: 700px;
        background: url(../../assets/2.png) no-repeat center;
    }
    .navbar {
        width: 108px;
        height: 22px;
        background-color: aliceblue;
        color: black;
        position: absolute;
        top: 440px;
        left: 122px;
    }

}

/*分辨率高于1440，采用下面的样式*/
@media  (min-width: 768px) {

    .nav {
        margin: 200px auto;
        position: relative;
        width: 900px;
        height: 290px;
        background: url(../../assets/1.png) no-repeat center;
    }

    .navbar {
        background-color: aliceblue;
        color: black;
        position: absolute;
        top: 106px;
        left: 785px;
    }

}